Struct Residue 

pub struct Residue<'f, T: MontStorage, P: Personality = Nct> { /* private fields */ }

A value in Field<T, P>, stored implicitly in Montgomery form.

The 'f lifetime brand ties this residue to its parent Field; the P parameter ties it to the parent’s algorithm personality. The borrow checker rejects code that uses a residue after its Field is dropped, or that mixes residues across personalities. See module docs for the covariance caveat.

Implementations

impl<T: MontStorage, P: Personality> Residue<'_, T, P>

pub fn mont_value(&self) -> &T

Returns a reference to the underlying Montgomery-form value.

Escape hatch. Intended for downstream specialization layers (e.g. Curve25519Field) that implement fast paths reading the raw limbs. General consumers should not call this — use the methods on Field instead.

impl<'f, T> Residue<'f, T, Ct>

where T: ConditionallySelectable + MontStorage,

pub fn cswap(choice: Choice, a: &mut Self, b: &mut Self)

Conditionally swap two residues in constant time.

If choice is set, a and b exchange Montgomery-form values; otherwise both are left unchanged. The operation is branchless.

This is the primitive used by Montgomery ladders (x25519 scalar multiplication, RSA blinded exponentiation). It is the only residue swap that should appear in such a ladder; std::mem::swap is not guaranteed to be branchless.

impl<'f, T> Residue<'f, T, Ct>

where T: ConstantTimeEq + MontStorage,

pub fn ct_eq(&self, other: &Self) -> Choice

Constant-time equality on the underlying Montgomery values.

Use in place of derived PartialEq on Ct paths where the equality outcome must not leak through timing (ML-KEM decapsulation tag check, ed25519 signature verification).

Trait Implementations

impl<'f, T: Clone + MontStorage, P: Clone + Personality> Clone for Residue<'f, T, P>

fn clone(&self) -> Residue<'f, T, P>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'f, T: Debug + MontStorage, P: Debug + Personality> Debug for Residue<'f, T, P>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'f, T: MontStorage, P: Personality> Drop for Residue<'f, T, P>

Available on crate feature zeroize only.

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl<'f, T: Eq + MontStorage, P: Eq + Personality> Eq for Residue<'f, T, P>

impl<'f, T: PartialEq + MontStorage, P: PartialEq + Personality> PartialEq for Residue<'f, T, P>

fn eq(&self, other: &Residue<'f, T, P>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<'f, T: PartialEq + MontStorage, P: PartialEq + Personality> StructuralPartialEq for Residue<'f, T, P>

impl<'f, T: MontStorage, P: Personality> Zeroize for Residue<'f, T, P>

Available on crate feature zeroize only.

fn zeroize(&mut self)

Zero out this object from memory using Rust intrinsics which ensure the zeroization operation is not “optimized away” by the compiler.

impl<'f, T: MontStorage, P: Personality> ZeroizeOnDrop for Residue<'f, T, P>

Available on crate feature zeroize only.